On Fri, Mar 11, 2022 at 06:13:27PM -0800, Dai Ngo wrote:
> Add callout function nfsd4_lm_lock_expired for lm_lock_expired.
> If lock request has conflict with courtesy client then expire the
> courtesy client and return no conflict to caller.
>
> Signed-off-by: Dai Ngo <dai.ngo@xxxxxxxxxx>
> ---
> fs/nfsd/nfs4state.c | 37 +++++++++++++++++++++++++++++++++++++
> 1 file changed, 37 insertions(+)
>
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index a65d59510681..583ac807e98d 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -6578,10 +6578,47 @@ nfsd4_lm_notify(struct file_lock *fl)
> }
> }
>
> +/**
> + * nfsd4_lm_lock_expired - check if lock conflict can be resolved.
> + *
> + * @fl: pointer to file_lock with a potential conflict
> + * Return values:
> + * %false: real conflict, lock conflict can not be resolved.
> + * %true: no conflict, lock conflict was resolved.
> + *
> + * Note that this function is called while the flc_lock is held.
> + */
> +static bool
> +nfsd4_lm_lock_expired(struct file_lock *fl)
> +{
> + struct nfs4_lockowner *lo;
> + struct nfs4_client *clp;
> + bool rc = false;
> +
> + if (!fl)
> + return false;
> + lo = (struct nfs4_lockowner *)fl->fl_owner;
> + clp = lo->lo_owner.so_client;
> +
> + /* need to sync with courtesy client trying to reconnect */
> + spin_lock(&clp->cl_cs_lock);
> + if (test_bit(NFSD4_CLIENT_EXPIRED, &clp->cl_flags))
> + rc = true;
> + else {
> + if (test_bit(NFSD4_CLIENT_COURTESY, &clp->cl_flags)) {
> + set_bit(NFSD4_CLIENT_EXPIRED, &clp->cl_flags);
> + rc = true;
> + }
> + }
I'd prefer:
if (test_bit(NFSD4_CLIENT_COURTESY, &clp->cl_flags))
set_bit(NFSD4_CLIENT_EXPIRED, &clp->cl_flags);
if (test_bit(NFSD4_CLIENT_EXPIRED, &clp->cl_flags))
rc = true;
Same result, but more compact and straightforward, I think.
--b.
> + spin_unlock(&clp->cl_cs_lock);
> + return rc;
> +}
> +
> static const struct lock_manager_operations nfsd_posix_mng_ops = {
> .lm_notify = nfsd4_lm_notify,
> .lm_get_owner = nfsd4_lm_get_owner,
> .lm_put_owner = nfsd4_lm_put_owner,
> + .lm_lock_expired = nfsd4_lm_lock_expired,
> };
>
> static inline void
> --
> 2.9.5
